Hello, how did you solve your problem? It doesn't work for me.
I did put the launcher.dat and mset_eur.cia (I have a PAL French N3DSXL) on the internal mSD of my console. I booted the GW mode via the Zelda exploit, did the install of NVRAM successfuly (eur version), did boot on GW mode, launched the devmenu.3ds, from there I installed the mset_eur.cia successfuly again, but when I reboot and try to launch the exploit from the DS profil, it just.. opens the DS profile menu.
I retried 3 times but really I don't understand I followed every steps carefully.
Thanks if you can help me.
EDIT: I fixed it too!